Neural factors responsible for reversal of functional and morphological claw and claw muscle asymmetry in snapping shrimp will be sought. Cellular switches which trigger size changes in motor neurons will be timed and correlated with the time of onset of changes in claw asymmetry. Motor impulse patterns will be monitored in claws during asymmetry reversal and muscle transformation. Size and position changes in motor neurons will be monitored during asymmetry reversal by plots on a three-dimensional coordinate system. Light chain subunits in transformed and untransformed muscle will be analyzed by SDS-PAGE techniques and autoradiography of two-dimensional slab gels.